Inhibition of Hormone Release Match the type of hormonal inhibition on the left with the appropriate example on the right. 1. Hormonal stimuli. 2. Neural stimuli. 3. Humoral stimuli.
The Correct Answer and Explanation is:
Here’s how the types of hormonal inhibition correspond to the examples provided:
- Hormonal Stimuli: This refers to the release of one hormone triggering the release of another hormone. An example is the inhibition of thyroid-stimulating hormone (TSH) when thyroid hormones (T3 and T4) are at high levels. The hypothalamus and anterior pituitary decrease the secretion of TSH due to the negative feedback mechanism from the elevated thyroid hormones, thus inhibiting further release.
- Neural Stimuli: This type of inhibition involves the nervous system directly stimulating hormone release. An example is the release of epinephrine (adrenaline) by the adrenal glands in response to stress signals sent from the brain (such as the sympathetic nervous system). In this case, the release of epinephrine is regulated by neural inputs and will be inhibited once the stressor subsides.
- Humoral Stimuli: This type refers to the release of hormones in response to changes in the levels of certain ions or nutrients in the blood. For instance, insulin secretion by the pancreas is stimulated by increased blood glucose levels (humoral stimuli). However, when blood glucose levels drop, the secretion of insulin is inhibited, which helps to maintain homeostasis.
Explanation:
- Hormonal stimuli are part of a complex network of feedback systems in the body. These systems rely on the hormone levels themselves to regulate secretion. For example, high levels of thyroid hormones inhibit further release of TSH to prevent overproduction.
- Neural stimuli involve direct regulation by the nervous system. These stimuli tend to be rapid and transient, as they are typically linked to acute responses like stress or changes in environmental conditions.
- Humoral stimuli act based on the levels of substances in the bloodstream, such as glucose, calcium, or sodium. They are essential for maintaining the body’s internal environment (homeostasis) and respond to changes in nutrient or ion concentrations.
Understanding these mechanisms is crucial in the study of physiology, especially when discussing how the body regulates its hormone levels and maintains balance.
